The goal of this project is to complete the development of a new family of interfaces between chromatography and mass spectrometry which provide multichannel element- and isotope-selective detection capabilities. The approach is based on combining a new "Universal Interface" (UI) for LC with a micro-wave powered "Chemical Reaction Interface" (CRI) and coupling the output to electron ionization (EI) mass spectrometry (MS). The UI vaporizes the LC solvent and efficiently removes the solvent vapor while transmitting most of the relatively nonvolatile solutes as an aerosol in dry helium or other suitable carrier. The CRI was originally developed to accept gas chromatographic effluents, but work completed during phase I has demonstrated that addition of the UI makes coupling with HPLC feasible as well. In phase II research will be aimed at improving the sensitivity of the LC-CRIMS system so that the detection limits approach those attained with GC. The overall goal of the phase II effort is to complete the development of practical LC-CRIMS systems and to establish their performance characteristics. By the end of phase II we expect to have fully developed and proved LC-CRIMS instrumentation. In Phase III CRIMS systems will be made commercially available, both as complete systems and as less-expensive interfaces for standard EI mass spectrometers. Successful completion of this project will provide a new family of analytical instruments with unique capabilities for many biochemical, pharmacological, and environmental applications.